BUR #21788 has been approved by @evazion.
create implication racing_miku_(2024) -> racing_miku
create implication yuzuki_yukari_(a.i._voice_2) -> yuzuki_yukari
create implication kizuna_akari_(a.i._voice_2) -> kizuna_akari
create implication melon_yukari -> yuzuki_yukari
Updates for vocal synth implications.